Comet tails

. Telescopic photograph of Comet Mrkos taken in August 1957, showing the straight, well-defined ion tail and the more diffuse, slightly curved dust tail. Both comet tails point away from the Sun. The electrified solar wind deflects the charged ions and accelerates them to high velocities, creating the relatively straight ion tails. The radiation pressure of sunlight suffices to blow away the unionized comet dust particles, forming a broad arc that can resemble a scimitar. (Courtesy of Lick Observatory.)